/*
 * Copyright [2021-present] [ahoo wang <ahoowang@qq.com> (https://github.com/Ahoo-Wang)].
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *      http://www.apache.org/licenses/LICENSE-2.0
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package me.ahoo.cosec.api.context

interface Attributes<SOURCE : Attributes<SOURCE, KEY, VALUE>, KEY, VALUE> {
    val attributes: Map<KEY, VALUE>
    fun withAttributes(attributes: Map<KEY, VALUE>): SOURCE

    @Suppress("ReturnCount")
    fun mergeAttributes(additionalAttributes: Map<KEY, VALUE>): SOURCE {
        if (additionalAttributes.isEmpty()) {
            @Suppress("UNCHECKED_CAST")
            return this as SOURCE
        }
        if (this.attributes.isEmpty()) {
            return withAttributes(attributes = additionalAttributes)
        }
        val mergedAttributes = buildMap(attributes.size + additionalAttributes.size) {
            putAll(additionalAttributes)
            putAll(attributes)
        }
        return withAttributes(attributes = mergedAttributes)
    }
}
